It'd be hilarious if DI3 turned out to be not Star Wars.
Either way, Disney never mentioned or even hinted they were doing any DI related announcements at this. The game hasn't even been officially confirmed to exist yet! Getting all excited over expected announcements that didn't happen is all on y'all.
There are probably gigantic marketing decisions involved in making or not making announcements. Maybe they didn't want to clash with the release of Battlefront's trailer. EA does have a mostly exclusive partnership to make Star Wars games now, so there might be some licensing issues with having another major release taking some of their spotlight.
And that's all still assuming that DI 3 is Star Wars related - which has not been confirmed yet!